Keeping guppy alive is easy, try this method:

1. No need air filter, no need air pump.
2. Plastic container, transparent type as sell at fish shop, cost RM8 ~ RM25.
3. Minimize water level, approx 6cm height will do.
4. Control population... ^^, depends on tank size, ok!
5. Feed twice a day, but have to make sure they finish it.
6. Change water 3 days once, fully change. Water must be pre-treated.

P/S: Pre-treated water = normal tap water which has been process up to 3 days. Processes by air circulation, apply air pump..

Try this up.. guarantee survive.. ^^